Method of making mask pattern data and process for manufacturing the mask

ABSTRACT

Pattern data of a phase shift mask can be inspected: (101) by separating and laying out pattern data of a phase shift mask in an actual pattern data layer, an auxiliary pattern data layer and a phase shift pattern data layer; (102) by inspecting and correcting only the data of the actual pattern of the actual pattern data layer; (103) by making data of an estimated pattern estimated to be transferred to a semiconductor wafer from the data of the synthetic data of the correct actual pattern data, the auxiliary pattern data and the phase shift pattern data, which are inspected and corrected; and (104) by comparing the estimated pattern data and the actual pattern data to inspect the data of the auxiliary pattern and the phase shift pattern.

This application is a Division application of application Ser. No.07/886,403, filed May 21, 1992, now U.S. Pat. No. 5,458,998.

BACKGROUND OF THE INVENTION

The present invention relates to a method of making pattern data of amask and a technology for manufacturing a mask and, more particularly,to a technology for designing the layout of a mask pattern for anoriginal of a predetermined pattern forming a semiconductor integratedcircuit device.

In an ordinary mask of the prior art, a mask pattern formed over a masksubstrate is identical to a pattern to be formed over a semiconductorwafer by a designer.

For making data of the mask pattern, therefore, the data of the maskpattern to be formed over the mask substrate is inspected on whether ornot the geometric rule and electric rule of the pattern to be formedover the semiconductor wafer are satisfied. On the basis of thisinspection result, the data of the mask pattern is corrected by anoperator or computer so that it may match the design.

Incidentally, the layout design technology is disclosed on pp. 212 to214 of "Introduction to MOSLSI Design" issued in 1984 by Sangyo Tosho,for example.

BRIEF SUMMARY OF THE INVENTION

In recent years, the semiconductor integrated circuit device tends toreduce the sizes of elements and wiring lines to be formed over thesemiconductor wafer.

Accordingly, it is requested to improve the resolution of a pattern tobe transferred to the semiconductor wafer.

The technology for improving the resolution of the pattern to betransferred to the semiconductor wafer is exemplified by the phase shiftmethod.

This phase shift method is a technology for improving the resolution bymaking use of the mutual interference of transmission lights which aregiven a phase difference while transmitting through a phase shift mask.

In case of the phase shift method, the pattern formed over the masksubstrate and the pattern to be formed over the semiconductor wafer maybe partially different, as will be described with reference to FIGS. 37to FIG. 42.

FIG. 37 shows a pattern 50 to be formed over the semiconductor wafer.This pattern 50 is formed of patterns 50a to 50d, of which the patterns50a and 50d and the patterns 50b and 50d are sized to the minimum ofabout 0.35 μm that cannot be resolved by an i-ray, for example.

Now, it is assumed that a pattern 51 (51a to 51d) formed, as shown inFIG. 38, on the mask substrate be identical in shape to the pattern tobe formed over the semiconductor wafer, as shown in FIG. 37.

It is also assumed that phase shift pattern films 52a and 52b bearranged over the patterns 51a and 51c of that pattern 51, as shown inFIG. 39.

In this case, there arises no problem because the ray having transmittedthrough the patterns 51a and 51c arranged with the phase shift patternfilms 52a and 52b and the ray having transmitted through the patterns51b and 51d without the phase shift pattern films 52a and 52b havephases opposite to each other.

Since, however, the ray having transmitted through the pattern 51b andthe ray having passed through the pattern 51b are in phase with eachother, an unnecessary pattern will be transferred between the patterns51b and 51d. This problem cannot be avoided merely by changing thearrangement of the phase shift pattern films 52a and 52b.

In this case, therefore, the pattern 51 formed over the mask substrateis changed, for example, in the following manner.

Specifically, as shown in FIG. 40, there is arranged between thepatterns 51b and 51d an auxiliary pattern 53a for connecting thepatterns 51b and 51d to form a pattern composed of three wiring patterns54a to 54c running in parallel, as shown in FIG. 41.

As shown in FIG. 42, moreover, patterns 54a and 54c of a pattern 54 areindividually arranged thereover with the phase shift pattern films 52aand 52b, and a pattern 54b is arranged thereover with a phase shiftpattern film 52c in the position which is arranged with the auxiliarypattern 58a (as shown in FIG. 40).

Thus, since the ray having transmitted through the pattern 54b has aphase difference between the regions having the phase shift pattern film52c and not, the pattern 50 shown in FIG. 37 can be transferred to thesemiconductor wafer.

Thus, in case of the phase shift mask, the pattern 54 formed over themask substrate and the pattern 50 to be formed over the semiconductorwafer are partially different.

Incidentally, assuming that the pattern formed over the mask substrateand the pattern to be formed over the semiconductor wafer be identical,the data of the pattern formed over the mask substrate is inspected onwhether or not the geometric rule and electric rule of the pattern to beformed over the semiconductor wafer are satisfied.

If, however, the inspecting method is to be applied to the data makingof the mask pattern of the phase shift mask, the pattern 54b on the masksubstrate, as shown in FIG. 42, is decided to be shorted, although it iscorrect. This is because the pattern has to be separated over thesemiconductor wafer.

Specifically, in case the pattern formed over the mask substrate and thepattern to be formed over the semiconductor wafer are different as inthe phase shift mask, for example, there arises a problem that the dataof the mask pattern cannot be inspected when it is made.

The present invention has been conceived in view of the above-specifiedproblems and has an object to provide a technology capable of inspectingthe propriety of the pattern data of a phase shift mask.

The foregoing and other objects and novel features of the presentinvention will become apparent from the following description to be madewith reference to the accompanying drawings.

The representatives of the invention to be disclosed herein will bebriefly summarized in the following.

According to a first invention, there is provided a method of makingpattern data of a mask, which comprises: a step of laying out, when thepattern data of a mask having a mask pattern and a phase shift patternon a mask substrate are to be made, said pattern data separately in anactual pattern data layer having data of an actual pattern, in anauxiliary pattern data layer having data of an auxiliary pattern, and ina phase shift pattern data layer having data of a phase shift pattern; afirst inspection step of inspecting the propriety of only said actualpattern and repeating the inspection and correction till said actualpattern becomes good; a step of making data of an estimated patternestimated to be transferred to said substrate by a synthetic pattern ofthe actual pattern, auxiliary pattern and phase shift pattern, which areformed through said first inspection step; and a second inspection stepof comparing said estimated pattern and the actual pattern after saidfirst inspection step and repeating the inspection and correction tillthey become coincident.

According to a second invention, there is provided a method of makingpattern data of a mask, wherein said phase shift pattern data layer isdivided into two or more data layers.

According to the above-specified first invention, by separating thepattern data of the phase shift mask into the actual pattern data layer,the auxiliary pattern data layer and the phase shift pattern data layerand by inspecting only the actual pattern, whether or not the actualpattern formed by designing the layout of the pattern of the phase shiftmask is good can be decided by using the inspection method of the priorart as it is.

Moreover, a synthetic pattern of the inspected actual pattern, theauxiliary pattern and the phase shift pattern is formed to form theestimated pattern to be formed over the semiconductor wafer or the likeby the synthetic pattern, so that the propriety of the auxiliary patternand the phase shift pattern of the phase shift mask can be decided bycomparing The estimated pattern and the inspected actual pattern.

According to the above-specified second invention, the pattern data inthe phase shift pattern data layer, for example, is further separated bythe difference in the graphic processing so that the separated datalayers can be independently processed to facilitate the data processing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart for explaining a method of making pattern data ofa mask according to one embodiment of the present invention;

FIG. 2 is a diagram for explaining a data storage state of a layoutlayer during the pattern data making step;

FIG. 3 is a top plan view showing an essential portion of an example ofthe pattern to be transferred to a semiconductor wafer;

FIG. 4 is a diagram for explaining the data storage state of a layoutlayer during the pattern data making step;

FIG. 5 is a diagram schematically showing examples of the individualpatterns stored in a pattern data layer;

FIG. 6 is a diagram schematically showing examples of the individualpatterns stored in a pattern data layer;

FIG. 7 is a diagram for explaining a step of comparing an estimatedpattern and an actual pattern in case the pattern of FIG. 3 is to beformed;

FIG. 8 is a diagram for explaining a step of comparing an estimatedpattern and an actual pattern in case the pattern of FIG. 3 is to beformed;

FIG. 9 is a diagram for explaining a step of comparing an estimatedpattern and an actual pattern in case the pattern of FIG. 3 is to beformed;

FIG. 10 is a top plan view showing an essential portion of a maskpattern formed over a mask substrate;

FIG. 11 is a section taken along line A--A of FIG. 10;

FIG. 12 is a diagram for explaining a broadening process;

FIG. 13 is a top plan view showing an essential portion of a maskpattern and a phase shift pattern formed over the mask substrate;

FIG. 14 is a section taken along line B--B of FIG. 13;

FIG. 15 is a diagram for explaining a step of comparing the estimatedpattern and the actual pattern in case the pattern of FIG. 3 is formed;

FIG. 16 is a diagram for explaining the broadening process;

FIG. 17 is a top plan view showing an essential portion of a maskpattern and a phase shift pattern formed over the mask substrate;

FIG. 18 is a section taken along line C--C of FIG. 17;

FIG. 19 is a top plan view showing an essential portion to betransferred to the semiconductor wafer for explaining a method of makingpattern data of a mask according to another embodiment of the presentinvention;

FIG. 20 is a diagram for explaining a step of comparing the estimatedpattern and the actual pattern in case the data of the pattern of FIG.19 is made;

FIG. 21 is a diagram for explaining a step of comparing the estimatedpattern and the actual pattern in case the data of the pattern of FIG.19 is made;

FIG. 22 is a diagram for explaining a step of comparing the estimatedpattern and the actual pattern in case the data of the pattern of FIG.19 is made;

FIG. 23 is a diagram for explaining a step of comparing the estimatedpattern and the actual pattern in case the data of the pattern of FIG.19 is made;

FIG. 24 is a diagram for explaining a step of comparing the estimatedpattern and the actual pattern in case the data of the pattern of FIG.19 is made;

FIG. 25 is a top plan view showing an essential portion of a maskpattern and a phase shift pattern for forming the pattern of FIG. 19;

FIG. 26 is a section taken along line D--D of FIG. 25;

FIG. 27 is a top plan view showing an essential portion to betransferred to the semiconductor wafer for explaining a method of makingpattern data of a mask according to still another embodiment of thepresent invention;

FIG. 28 is a diagram for explaining a step of comparing the estimatedpattern and the actual pattern in case the data of the pattern of FIG.27 is made;

FIG. 29 is a diagram for explaining a step of comparing the estimatedpattern and the actual pattern in case the data of the pattern of FIG.27 is made;

FIG. 30 is a diagram For explaining a step of comparing the estimatedpattern and the actual pattern in case the data of the pattern of FIG.27 is made;

FIG. 31 is a top plan view showing an essential portion of the maskpattern and the phase shift pattern for forming the pattern of FIG. 27;

FIG. 32 is a section taken along line E--E of FIG. 31;

FIG. 33 is a diagram for explaining a step of comparing the estimatedpattern and the actual pattern in case the data of the pattern of FIG.27 is made;

FIG. 34 is a top plan view showing an essential portion of the maskpattern and the phase shift pattern for forming the pattern of FIG. 27;

FIG. 35 is a section taken along line K--K of FIG. 34;

FIG. 36 is a flow chart for explaining a method of making pattern dataof a mask according to another embodiment of the present invention;

FIG. 37 is a diagram for explaining that a mask pattern over a phaseshift mask and a pattern to be formed over a semiconductor wafer aredifferent;

FIG. 38 is a diagram for explaining that a mask pattern over a phaseshift mask and a pattern to be formed over a semiconductor wafer aredifferent;

FIG. 39 is a diagram for explaining that a mask pattern over a phaseshift mask and a pattern to be formed over a semiconductor wafer aredifferent;

FIG. 40 is a diagram for explaining that a mask pattern over a phaseshift mask and a pattern to be formed over a semiconductor wafer aredifferent;

FIG. 41 is a diagram for explaining that a mask pattern over a phaseshift mask and a pattern to be formed over a semiconductor wafer aredifferent; and

FIG. 42 is a diagram for explaining that a mask pattern over a phaseshift mask and a pattern to be formed over a semiconductor wafer aredifferent;

DETAILED DESCRIPTION OF THE INVENTION [Embodiment 1]

FIG. 1 is a flow chart for explaining a method of making pattern data ofa mask according to one embodiment of the present invention; FIG. 2 is adiagram for explaining a data storage state of a layout layer during thepattern data making step; FIG. 3 is a top plan view showing an essentialportion of an example of the pattern to be transferred to asemiconductor wafer; FIG. 4 is a diagram for explaining the data storagestate of a layout layer during the pattern data making step; FIGS. 5 and6 are diagram schematically showing examples of the individual patternsstored in pattern data layers; FIGS. 7 to 9 and FIG. 15 are diagrams forexplaining steps of comparing estimated patterns and actual patterns incase the pattern of FIG. 3 is to be formed; FIG. 10 is a top plan viewshowing an essential portion of a mask pattern formed over a masksubstrate; FIG. 11 is a section taken along line A--A of FIG. 10; FIGS.12 and 16 are diagrams for explaining broadening processes; FIGS. 13 and17 are top plan views showing essential portions of mask patterns andphase shift patterns formed over the mask substrate; FIG. 14 is asection taken along line B--B of FIG. 13; and FIG. 18 is a section takenalong line C--C of FIG. 17.

The mask pattern data making method according to the present embodiment1 is exemplified by a pattern data making method of a phase shift mask.

FIG. 2 is a diagram for explaining a data storage state of a layoutlayer 1 during the pattern data making step of the phase shift mask ofthe present embodiment 1.

As shown in FIG. 2, the layout layer 1 is divided into a plurality ofpattern data layers 2 to 5.

At this stage, each of the pattern data layers 2 to 5 is a data layerfor manufacturing one sheet of phase shift mask.

On the other hand, the pattern data layer 3, for example, is separatedinto pattern data layers 3a and 3b in accordance with the necessity fora data processing. The pattern data layer 4 is also separated intopattern data layers 4a and 4b in accordance with the necessity for adata processing.

In the present embodiment 1, for example, the following procedure istaken from that state. In the following description, the pattern datamaking method of the phase shift mask of the present embodiment 1 willbe described in accordance with the steps of FIG. 1 with reference toFIGS. 8 to 18 by exemplifying the case in which wiring patterns 6a to 6dshown in FIG. 3 are to be transferred to a (not-shown) semiconductorwafer.

First of all, in the present embodiment 1, the pattern data layers 2,3a, 3b, 4a, 4b and 5 are separated into and laid out (at Step 101) in anactual pattern data layer 7, an auxiliary pattern data layer 8 and aphase shift pattern layer 9.

The actual pattern data layer 7 is one which is stored with the data ofan actual pattern having the same shape as that to be formed over thesemiconductor wafer.

Moreover, the auxiliary pattern data layer 8 is one which is stored withthe data of an auxiliary pattern needed for forming a pattern over thesemiconductor wafer although not transferred to the semiconductor wafer.

Still moreover, the phase shift pattern data layer 9 is one which isstored with the data of a phase shift pattern for establishing a phasedifference in a ray to transmit therethrough.

In case the wiring patterns 6a to 6d shown in FIG. 3 are to be formed,for example, an actual pattern data layer 7a, an auxiliary pattern datalayer 8a and a phase shift pattern data layer 9a are desired to bestored respectively with the data of an actual pattern F1, an auxiliarypattern H1 and a phase shift pattern S shown in FIG. 5, for example.

In the present embodiment 1, moreover, the phase shift pattern datalayer 9a is divided into first and second phase shift pattern datalayers 9a₁, and 9a₂, as shown in FIGS. 4 and 6.

This is because a first phase shift pattern S1 and a second phase shiftpattern S2 of FIG. 6 have different broadened extents. These broadeningextents are the difference between the mask size and the mask size,i.e., the scale-up and -down of the pattern on the data.

Since the first and second phase shift patterns S1 and S2 are differentin the scale-up extent and manner, it is easier to process the datalayer if the layer is so divided that the individuals can beindependently processed.

For example, the first phase shift pattern S1 may be isotropicallyscaled up in its entirety. However, the second phase shift pattern S2may have different scale-up extents in the transverse and longitudinaldirections in FIG. 6.

This is because the transverse size of the second phase shift pattern S2of FIG. 6 is set in a manner to anticipate the matching margin with themask pattern, whereas the longitudinal size of the same is set on thebasis of the size between the patterns 6b and 6d shown in FIG. 3.

However, the broadening procedure had better be performed by laying outthe actual pattern, which is extracted on-line from the actual patterndata layer 7a, as the first phase shift pattern S1 to form a correctphase shift pattern S, and subsequently by forming the graphic data of aphase shift pattern on the basis of the data of the correct phase shiftpattern S. Then, this performance could eliminate the wastefulness.

These actual pattern data layer 7, auxiliary pattern data layer 8 andphase shift pattern data layer 9 can have their pattern data processedindividually and independently and synthesized.

And, these pattern data or the like can be displayed on a (not-shown)display and and visualized.

Subsequently, only the data of the actual pattern of the actual patterndata layer 7 is inspected (at 102) as by the conventional method whetheror not the geometric rule, the electric rule and so on are satisfied.

If NOT, the data of the actual pattern are repeatedly corrected andinspected till the data are satisfied.

Incidentally, the improper portion, which is found as a result of theinspection, is displayed on the aforementioned display.

Moreover, the data of the auxiliary pattern and the phase shift patternare corrected if they are required for the corrections by the correctionof the actual pattern.

In case the actual pattern data satisfy the inspection, the data of thecorrect actual pattern, the auxiliary pattern and the phase shiftpattern, which were obtained through the inspection and correctionsteps, are composed to make (at Step 103) data of an estimated patternto be transferred to the semiconductor wafer on the basis of the data ofthe synthetic pattern.

Subsequently, the data of the estimated pattern and the data of thecorrect actual pattern obtained through the aforementioned inspectionand correction steps are compared (at Step 104).

If the data of the estimated pattern and the actual pattern fail to becoincide, the correction and inspection of the pattern data are repeatedtill the coincidence is obtained.

Let it be assumed that the data of the actual pattern F1, the auxiliarypattern H1 and the phase shift pattern S shown in FIG. 7 be made, forexample. In this case, the following data processing is performed.

First of all, for example, there are made the data of a synthesizedpattern SY2 of the actual pattern F1 and the auxiliary pattern H1, andthe data of a synthetic pattern SY3 of the first phase shift pattern S1and the second phase shift pattern.

Subsequently, on the basis of the data of the synthetic pattern SY4, thedata of an estimated pattern EX1, as shown in the same Figure, are madeand compared with the data of the actual pattern F1.

Since, in this case, the data of the estimated pattern EX1 and the dataof the actual pattern F1 are not coincident, it can be decided thateither or both of the auxiliary pattern H1 and the phase shift pattern Sare erroneous. Here, the second phase shift pattern has an error and iscorrected.

In the absence of the auxiliary pattern, as shown in FIG. 8, acontradiction to the definition of the phase shift method occurs to makeneither the data of the synthetic pattern nor the pattern of theestimated pattern of the actual pattern, the auxiliary pattern and thephase shift pattern.

Here, the data of the auxiliary pattern and the first phase shiftpattern are erroneous and are corrected.

In case, on the other hand, the data of the estimated pattern and theactual pattern are coincident, the graphic data of the mask pattern aremade on the basis of the data of the synthetic pattern of the actualpattern and the auxiliary pattern, and the graphic data of the phaseshift pattern are made on the basis of the synthetic pattern of thefirst and second phase shift pattern (at Step 105).

From those graphic data, moreover, the mask pattern and the phase shiftpatterns are formed over the mask substrate by the photolithographytechnology to manufacture the phase shift mask (at Step 106).

Let it be assumed that the data of the actual pattern F1, the auxiliarypattern H1 and the phase shift pattern S of FIG. 9 be made. This is inthe desired state shown in FIG. 5. Then, the following data processingis accomplished.

First of all, the data of a synthetic pattern SY6 are made from the dataof the synthetic pattern SY2 of the actual pattern F1 and the auxiliarypattern H1 and the data of a synthetic pattern SYS of the first phaseshift pattern S1 and the second phase shift pattern S2.

Subsequently, the data of an estimated pattern EX2 made on the basis ofthe data of the synthetic pattern SY6 are compared with the data of theactual pattern F1.

Since, in this case, the data of the estimated pattern EX2 and the dataof the actual pattern F1 are coincident, it can be decided that the dataof the auxiliary pattern HI and the phase shift pattern S are correct.

Thus, the graphic data of the mask pattern are made on the basis of thedata of the synthetic pattern SY2 of the actual pattern F1 and theauxiliary pattern H1.

On the basis of the graphic data thus made of the mask pattern,moreover, a mask pattern 10 shown in FIGS. 10 and 11 is formed over themask substrate 11 by the photolithography technology or the like.

The mask pattern 10 is one for forming hatched shielding regions 10a andtransmitting regions 10b on a mask substrate 11. The shielding regions10 are made of chromium (Cr) or the like. On the other hand, the masksubstrate 11 is made of quartz or the like.

Moreover, the graphic data of the phase shift pattern are made on thebasis of the data of the synthetic pattern SY5 of the first and secondphase shift patterns S1 and S2.

When the graphic data of the phase shift pattern are to be made, thedata of the first and second phase shift patterns S1 and S2 arebroadened to different extents to synthesize their pattern data so thatthe graphic data of the phase shift pattern are made on the basis of thedata of the synthetic pattern SY7.

On the basis of the graphic data thus made of the phase shift pattern,moreover, a phase shift pattern film 12a is formed in a predeterminedposition on the mask substrate 11 by the photolithography technology, asshown in FIGS. 13 and 14, to manufacture a phase shift mask 13.

Incidentally, the presence and absence of the phase shift pattern film12a can be reversed and arranged on the mask substrate 11.

In case, on the other hand, the data of the actual pattern F1, theauxiliary pattern H1 and the phase shift pattern S shown in FIG. 15 aremade, the data of the estimated pattern EX2 and the actual pattern F1are caused to be coincident by performing a process similar to theaforementioned one.

In this case, moreover, the graphic data of the mask pattern are made onthe basis of the data of the synthetic pattern SY2 of the actual patternF1 and the auxiliary pattern H1.

On the other hand, the graphic data of the phase shift pattern are madeon the basis of the data of a synthetic pattern SY8 of the first andsecond phase shift patterns S1 and S2.

In this case, when the graphic data of the phase shift pattern are to bemade, as shown in FIG. 16, the data of the first and second phase shiftpatterns S1 and S2 are broadened to different extents so that thegraphic data of the phase shift pattern are made on the basis of thedata of the synthetic pattern SY9.

On the basis of the graphic data thus made of the mask pattern and thephase shift pattern, moreover, the mask pattern 10 and a phase shiftpattern film 12b shown in FIGS. 17 and 18 are formed over the masksubstrate 11 by the photolithography technology to manufacture the phaseshift mask 13.

Incidentally, the presence and absence of the phase shift pattern film12b can be reversed and arranged on the mask substrate 11.

Thus, the following effects can be attained according to the presentembodiment 1.

(1) Since the layout layer 1 of the phase shift mask is separated intothe actual pattern data layer 7, the auxiliary pattern data layer 8 andthe phase shift pattern data layer 9 so that the propriety of the dataof the actual pattern only is inspected, the propriety of the actualpattern data of the pattern data of the phase shift mask can be decidedby using the inspecting method of the prior art as it is.

Moreover, the data of the synthetic pattern of the inspected actualpattern, the auxiliary pattern and the phase shift pattern are made tomake the estimated pattern to be formed over the semiconductor wafer sothat the propriety of the data of the auxiliary pattern and the phaseshift pattern of the phase shift mask can be decided by comparing thedata of the estimated pattern and the data of the inspected actualpattern.

As a result, the propriety of the pattern data of the phase shift maskcan be inspected.

(2) Thanks to the aforementioned effect (1), the reliability of thepattern data of the phase shift mask 13 can be improved.

(3) Since the pattern data in the pattern data layer can be furtherseparated in dependence upon the difference in the graphic processingsuch as the broadening, the separated data can be independentlyprocessed to facilitate the data processing so that the automaticprocessing by a computer or the like can be promoted.

[Embodiment 2]

FIG. 19 is a top plan view showing an essential portion to betransferred to the semiconductor wafer for explaining a method of makingpattern data of a mask according to another embodiment of the presentinvention; FIGS. 20 to 24 are diagrams for explaining steps of comparingthe estimated patterns and the actual patterns in case the pattern ofFIG. 19 is formed; FIG. 25 is a top plan view showing an essentialportion of a mask pattern and a phase shift pattern for forming thepattern of FIG. 19; and FIG. 26 is a section taken along line D--D ofFIG. 25.

In the present embodiment 2, the method of forming pattern data of amask will be described following the steps of FIG. 1 with reference toFIGS. 19 to 26 by exemplifying the case in which wiring patterns 6e and6f shown in FIG. 19 are to be transferred to a semiconductor wafer, forexample.

Incidentally, in the present embodiment 2, the wiring patterns 6e and 6fare exemplified by patterns having such a line width about 1 μm as canbe resolved by the i-ray and have a spacing of about 0.35 μm.

In this case, the auxiliary pattern need not be formed, and the presentembodiment 2 will be described in case of no auxiliary pattern.

Moreover, the present embodiment 2 have their Steps 101 and 102 of FIG.1 shared with those of the foregoing embodiment 1 and will be describedfrom the Step 103 of FIG. 1.

Let it be assumed that the data of an actual pattern F2 and a phaseshift pattern S3 shown in FIG. 20 be made, namely, that the phase shiftpattern S3 be deficient. In this case, the following data processingwill be performed.

First of all, like the foregoing embodiment 1, the data of an estimatedpattern EX3 made on the basis of the data of a synthetic pattern SY10 ofthe actual pattern F2 and the phase shift pattern S3 are compared (atSteps 103 and 104) with the data of the actual pattern F2.

Since, in this case, the data of the estimated pattern EX3 and the dataof the actual pattern F2 are not coincident, it can be decided that thephase shift pattern S3 has an error. Thus, this phase shift pattern S3is corrected.

It is further assumed that the data of the actual pattern F2 and a phaseshift pattern S4 shown in FIG. 21 be made. In this case, the phase shiftpattern S4 made is absolutely identical to the actual pattern F2.

This case is contrary to the definition of the phase shift method sothat the estimated pattern is not formed. As shown in FIG. 22, moreover,the case of no phase shift pattern is also contrary to the definition ofthe phase shift method so that the estimated pattern is not formed. Inthese cases, the phase shift pattern is corrected.

In case, on the other hand, the data of the actual pattern F2 and aphase shift pattern S5 shown in FIG. 23 or 24 are made, the data of anestimated pattern EX4 and the data of the actual pattern F2 arecoincident, if compared. Thus, it can be decided (at Steps 103 and 104).

In this case, therefore, the graphic data of the mask pattern are madeon the basis of the data of the actual pattern F2, and the graphic dataof the phase shift pattern are made (at Step 105) on the basis of thedata of the phase shift pattern S5.

Incidentally, when the graphic data of the phase shift pattern are to bemade, the data of the phase shift pattern S5 are broadened to apredetermined extent like the foregoing embodiment 1.

On the basis of the graphic data thus made of the mask pattern and thephase shift pattern, moreover, the mask pattern 10 and a phase shiftpattern film 12c shown in FIGS. 25 and 26 are formed over the masksubstrate 11 by the photolithography technology or the like tomanufacture the phase shift mask 13 (at Step 106).

Incidentally, the presence and absence of the phase shift pattern film12c can be reversed and arranged on the mask substrate 11.

According to the present embodiment 2 thus far described, the effectssimilar to those of the foregoing embodiment 1 can be achieved.

[Embodiment 3]

FIG. 27 is a top plan view showing an essential portion to betransferred to the semiconductor wafer for explaining a method of makingpattern data of a mask according to still another embodiment of thepresent invention; FIGS. 28 to 30 are diagrams for explaining steps ofcomparing the estimated patterns and the actual patterns in case thedata of the pattern of FIG. 27 is made; FIGS. 31, 33 and 34 are top planviews showing essential portions of the mask patterns and the phaseshift patterns for forming the pattern of FIG. 27; FIG. 32 is a sectiontaken along line E--E of FIG. 31; and FIG. 35 is a section taken alongline K--K of FIG. 34.

In the present embodiment 3, the mask pattern data making method will bedescribed along with the steps of FIG. 1 with reference to FIGS. 27 to35 by exemplifying the case in which a connection hole pattern 14 shownin FIG. 27 is to be transferred to the semiconductor wafer.

Incidentally, the present embodiment 3 have their Steps 101 and 102 ofFIG. 1 similar to those of the foregoing embodiment 1 and will bedescribed from the Step 103 of FIG. 1.

Let it be assumed that the data of actual pattern F3, auxiliary patternH2 and phase shift pattern S6 be made. In other words, the phase shiftpattern S6 is partially deficient.

This case is contrary to the definition of the phase shift method sothat no estimated pattern is formed. As shown in FIG. 29, moreover, thecase of no phase shift pattern is also contrary to the definition of thephase shift method so that no estimated pattern is formed. In Thesecases, therefore, the phase shift pattern is corrected.

On the other hand, let it be assumed that the data of the actual patternF3, the auxiliary pattern H2 of the phase shift pattern S6 shown in FIG.30 be made.

Since, in this case, the data of an estimated pattern EX5 and the dataof the actual pattern F2 are coincident, if compared, it can be decided(at Steps 103 and 104) that the auxiliary pattern H2 and the phase shiftpatterns S6 and S7 are correct.

In this case, therefore, the graphic data of the mask pattern are madeon the basis of the data of the synthesized pattern of the actualpattern F3 and the auxiliary pattern H2, and the graphic data of thephase shift pattern are made (at Step 105) are made on the basis of thedata of the phase shift pattern S7.

When the graphic data of the phase shift pattern are to be made, thedata of the phase shift pattern S7 are broadened to a predeterminedextent like the foregoing embodiment 1.

On the basis of the graphic data thus made of the mask pattern and thephase shift pattern, moreover, the mask pattern 10 and the phase shiftpattern film 12d shown in FIGS. 31 and 32 are formed over the masksubstrate 11 by the lithography technology or the like to manufacturethe phase shift mask 13 (at Step 106).

Incidentally, the presence and absence of the phase shift pattern film12d can be reversed and arranged over the mask substrate 11.

Even in case the data of the actual pattern F3, the auxiliary pattern H2and the phase shift pattern S8 shown in FIG. 33 are made, the data ofthe estimated pattern EXS and the data of the actual pattern F2 arecoincident if compared (at Steps 103 and 104).

In this case, too. the graphic data of The mask pattern are made on thebasis of the data of the synthesized pattern of the actual pattern F3and the auxiliary pattern H2, and the graphic data of the phase shiftpattern are made on the basis of the data of the phase shift pattern S8(at Step 105).

On the basis of the graphic data thus made of the mask pattern and thephase shift pattern, moreover, the mask pattern 10 and the phase shiftpattern film 12e shown in FIGS. 34 and 35 are formed over the masksubstrate 11 by the lithography technology or the like to manufacturethe phase shift mask 18 (at Step 106).

Incidentally, the presence and absence of the phase shift pattern film12e can be reversed and arranged over the mask substrate 11.

Thus in the present embodiment 3, too, effects similar to those of theaforementioned embodiment 1 can be achieved.

Although our invention has been specifically described in connectionwith the embodiments thereof, it should not be restricted to theforegoing embodiments 1 to 3 but can naturally be modified in variousmanners without departing from the gist thereof.

In the foregoing embodiments 1 to 3, for example, if the data of theestimated pattern and the data of the actual pattern are decided to beincoincident by their comparing inspection, the data of the auxiliarypattern or the phase shift patter are corrected, and the data of anestimated pattern are made again so that they may be inspectivelycompared with the data of the actual pattern. Despite of thisdescription, the present invention should not be limited thereto but canbe modified in the following various manners.

If the data of the estimated pattern and the data of the actual patternare decided to be incoincident, as shown in FIG. 36, it is decidedwhether or not the data of the actual pattern is to be corrected (atStep 104a)

Then, the data of the actual pattern are corrected, if necessary, andthe routine returns to the Step 101.

If the data of the actual pattern need not be corrected, on the otherhand, the data of the auxiliary pattern or the phase shift pattern arecorrected to return the routine to the Step 103.

In this case, the data of the estimated pattern and the data of theactual pattern are inspectively compared, and a change, if any, in thedata of the actual pattern can be responded to.

Another processing can be taken, as follows. If it is decided that thedata of the estimated pattern and the data of the actual pattern aredecided to be incoincident, the data of the auxiliary pattern or thephase shift pattern are corrected, and only the data of the actualpattern are inspected.

Moreover, an error, if found, in the data of the actual pattern iscorrected. If no error is found in the data of the actual pattern, onthe other hand, an estimated pattern is formed again so that its data isinspectively compared with the data of the actual pattern.

If, in this case, the actual pattern should be erroneously changed atthe time of a correction after the inspective comparison between thedata of the estimated pattern and the data of the actual pattern, theerror can be detected to improve the reliability of the pattern databetter.

The effects to be obtained from the representative of the inventiondisclosed herein will be briefly described in the following.

(1) According to the first invention thus far described, the patterndata of the phase shift mask is divided into the actual pattern datalayer, the auxiliary pattern data layer and the phase shift pattern datalayer, and only the actual pattern data is inspected. Thus, thepropriety of the actual pattern of the pattern data of the phase shiftmask can be decided, while the pattern data of the phase shift mask arebeing made, by using the inspection method of the prior art as it is.

Moreover, the synthetic pattern of the inspected actual pattern, theauxiliary pattern and the phase shift pattern is formed to form theestimated pattern to be formed over the semiconductor wafer or the likeby the synthetic pattern, and this estimated pattern and the inspectedactual pattern can be compared to decide the proprieties of theauxiliary pattern and the phase shift pattern of the phase shift mask.

In other words, the propriety of the pattern data of the phase shiftmask can be inspected to improve the reliability of the pattern data ofthe phase shift mask.

(2) According to the second invention thus far described, the patterndata in the phase shift pattern data layer, for example, is furtherseparated in dependence upon the graphic processing so that theseparated data layers can be independently processed. As a result, thedata processing can be facilitated to promote the automatic processingusing a computer.

By using the mask manufactured by the mask manufacturing process of thepresent invention, moreover, the transfer of a micro pattern can beprecisely executed by transferring the circuit pattern on the mask to asemiconductor circuit wafer or a semiconductor wafer with an exposurebeam such as the i-ray or a monochromatic ultraviolet ray of the excimerlaser by the step-and-repeat method using a lens scale-down projectionexposer.

What is claimed is:
 1. A method for making a phase-shifting mask inwhich an integrated circuit pattern on the phase-shifting mask is formedin accordance with a mask pattern drawing data, obtained from a maskpattern data at least having (1) an actual pattern data corresponding toat least one opening pattern or light shielding pattern on the mask tobe transferred onto an integrated circuit wafer, (2) an auxiliarypattern data not corresponding to the at least one opening pattern orlight shielding pattern on the mask to be transferred onto theintegrated circuit wafer, and (3) a shifter pattern data correspondingto at least one shifter pattern on the mask, by carrying out patterninspection and any necessary correction with an electronic graphicprocessing system which can memorize graphic data and can carry out adesired arithmetic process thereto, the method comprising steps of:(i)storing the mask pattern data in the electronic graphic processingsystem so as to be able to electronically independently access theactual pattern data, the auxiliary pattern data, and the shifter patterndata respectively; and then (ii) carrying out graphic inspection of themask pattern data stored in step (i).
 2. A method for making aphase-shifting mask according to claim 1, further comprising stepsof:(iii) based on the result of step (ii), carrying out any necessarycorrection of the mask pattern data; (iv) after steps (i) to (iii), inaccordance with the mask pattern data or a light shielding patterndrawing data for patterning at least one light shielding patternobtained therefrom, carrying out patterning of a light shielding film onthe mask for patterning the light shielding film; and (v) after steps(i) to (iii), in accordance with the mask pattern data or a shifterpattern drawing data for patterning at least one shifter patternobtained therefrom, carrying out patterning of a shifter film on themask for patterning the shifter film.
 3. A method for making aphase-shifting mask in which an integrated circuit pattern on thephase-shifting mask is formed in accordance with a mask pattern drawingdata, obtained from a mask pattern data at least having (1) an actualpattern data corresponding to at least one opening pattern or lightshielding pattern of the mask to be transferred onto an integratedcircuit wafer, (2) an auxiliary pattern data not corresponding to the atleast one opening pattern or light shielding pattern of the mask to betransferred onto the integrated circuit wafer, and (3) a shifter patterndata for patterning at least one shifter pattern of the mask, bycarrying out pattern inspection and any necessary correction withelectronic graphic processing which can memorize graphic data and cancarry out a desired arithmetic process thereto, the method comprisingsteps of:(i) storing the mask pattern data by electronic graphicprocessing so as to electronically independently access the actualpattern data, the auxiliary pattern data, and the shifter pattern datarespectively; and then (ii) carrying out graphic inspection of the maskpattern data stored in step (i).
 4. A method for making a phase-shiftingmask according to claim 3, further comprising steps of:(iii) based onthe result of step (ii), carrying out necessary correction to the maskpattern data by electronic data processing; (iv) after steps (i) to(iii), in accordance with the mask pattern data or a light shieldingpattern drawing data for patterning at least one light shielding patternobtained therefrom, carrying out patterning of a light shielding film ofthe mask for patterning the light shielding film; and (v) after steps(i) to (iii), in accordance with the mask pattern data or a shifterpattern drawing data for patterning at least one shifter patternobtained therefrom, carrying out patterning of the least one shifterpattern of the mask.
 5. A method for making a phase-shifting maskaccording to claim 3, wherein the step of carrying out graphicinspection of the mask pattern data stored in step (i) is performed byelectronic graphic processing.
 6. A method for making a phase-shiftingmask according to claim 3, wherein at least one of the actual patterndata, the auxiliary pattern data and the shifter pattern data aredivided into at least two sub-pattern data, the at least two sub-patterndata being stored by the electronic graphic processing so as to beelectronically individually accessed.
 7. A method for making aphase-shifting mask according to claim 6, wherein the shifter patterndata are divided into at least two sub-pattern data which are stored bythe electronic graphic processing so as to be electronicallyindividually accessed.